A keynote in public speaking is a talk that establishes a main underlying theme. In corporate or commercial settings, greater importance is attached to the delivery of a keynote speech or keynote address. The keynote establishes the framework for the following programme of events or convention agenda; frequently the role of keynote speaker[1] will include that of convention moderator. It will also flag up a larger idea – a literary story, an individual musical piece, or event.

Keynote speakers are often selected to raise interest in a particular event, such as a conference or large meeting sponsored by a corporation or association, and draw attendees to attend that program. Selecting a keynote speaker who is well known for his or her expertise in a particular field, or who has wide name recognition due to other accomplishments, will probably raise enthusiasm among prospective attendees for a meeting or conference. Increasingly the word keynote is being used as a synonym for plenary session or "invited talk," with some conferences having an opening keynote, a closing keynote, and many other keynotes.

A keynote speaker may work independently, be represented by a speakers bureau, or by a new crowdsourced model such as the speakerwiki website. In the event that a speaker is represented by a traditional speakers bureau, a commission, typically 25%–30%, is due; however, this is traditionally and ethically absorbed by the speaker rather than the client so that the fee remains flat and transparently priced to the client.[3]